Harrow



gular frame, A, in which are mounted trans- UNITED STATES PATENT OEEICE.A

JOHN UNDERwooD, or sIHEEIDAN, INDIANA.

HARROW.

SPECIFICATION forming part of Letters Patent No. 354,497, dated December 14, 1886.

Application led September 13, 1886. Serial No. 213,393.

To @ZZ whom it may concern.:

Be it known that I, JoIIN UNDERwooD, a citizen of the United States, residing at Sheridan, in the county of Hamilton and State of Indiana, have invented a new and useful Imthat side draft on the harrow may be avoided and the earth raised and turned as the harrow' moves forward, the said blades being so mounted in the barrow-frame that they may be quickly adjusted to cut to a greater or less depth,`at the will of the operator, all as hereinafter fully described.

IThe accompanying drawings illustrate my invention.

Figure lis a plan. Fig. 2 is a side elevation. Fig. 3 is a transverse section at a, Fig. l. Fig. 4. is a perspective View, on an enlarged scale, of a portion of the under side of the harrow, showing the position of the cutters in the r0ck-shaft and the manner in which they are secured thereto.

'Ihe harrow, as shown, consists of a rectanversely two rectangular rock-shafts, B and C, which are provided with journals c at each end, which rest in bearings formed in the sides of the frame A. Each of said rock-shafts is provided with a series of blades, d d, which extend backward and downward from the rockshafts. For the ,purpose of turning the rockshafts in their bearings, and thereby adjusting the free ends of the blades d to project a greater or less depth below the lower edge of the frame A, I secure rigidly to the upper side of the rock-shaft B a long lever, D, and to the upper side of the rock-shaft C, I secure a short lever, E, which levers are connected by means of a bar, F, which is pivoted at opposite ends to the respective levers.

Lever D is adjustably secured at different angles with bar F by means of a segment-bar, h, having a series of notches, i, which are en- (No model.)

gaged by a sliding pawl, j, mounted on the lever. A seat, H, may be mounted on bar F. Each of the blades d consists of a straight, thin, and narrow plate of steel. Said plates are set in grooves which pass diagonally across the under face of the rock-shaft, and are also inclined vertically thereto, as clearly shown in Fig. 4. The eect of this arrangement is,

to cause the blades in rock-shaft B,when lying in the same plane as the frame, to extend backward from the rock-shaft in such a position that a longitudinal section through the blade is inclined horizontally toward one side of the frame at an acute angle, while a transverse section through the blade is inclined vertically toward the opposite side of the frame at an acute angle to the perpendicular.

The blades in rock-shaft C are inclined oppositely to those in rock-shaft B. The blades are secured in their respective grooves by bolts e, the heads of which engage the lower edges of the blades. In operation lever D is drawn toward the seat, thereby throwing the back ends of both series of blades d below the lower edge of the frame. It will be observed that in this position of theblades transverse sections of the blades will approach a horizontal position, so that while the inclinationof longitudinal sections oi'` the blades will tend to cause the harrow to run to one side, the opposite inclination of the transverse sections will tend to cause it to run to the opposite side, and it therefore moves straight forward without side draft, the earth being raised and turned and thoroughly pulverized as the blades move through it. By this construction the necessity heretofore existing for twisting and curving the blades to a-given pattern is avoided, and any blade may therefore, when broken, be cheaply replaced.

I claim as my inventionl. In a harrow, the combination of the main frame, the rock-shaft mounted in said frame, a series of straight iiat blades secured to said rock-shaft and projecting therefrom and inclined horizontally and vertically in relation thereto, substantially as specified, and means for adjustably securing said rock-shaft in position. l l

2. In a harrow, the combination of the main IOC frame, two rock-shafts mounted in said frame, rock-shafts,l and oppositely inclined in the two means, substantially as shown and described, series,substantially as specified.` for securing the rock-shaft in different posir tions, and two series of straight fiat blades se- JOHN UNDER OOD' 5 cured to said rock-shafts and projecting there- Witnesses:

from, said blades being inclined horizontally A. PURsEL,

and vertically in relation to their respective WV. C. FURNAs. 

